What type of trap/drain is this?

I am trying to decide what type of trap/drain setup will work best for our kitchen sink. The drain will go straight down though the floor.

I was looking at our current setup in the rental house we are still in, it also goes in the floor and we have never had any trouble with it. It looks a little odd to me. I am no plumbing expert and cant find this configuration in any books I have.

What type of trap/drain is this?

What type of trap/drain is this?

Any harware or box store will have them.
Old steel drain pipes, or supplys?
At some point there all going to leak, plug up and need to be replaced.
Any time I have to replace the old drians I cut out the wall and reroute them into the wall.